First ever kazaa problem, must read

i was downloading a big .avi file, half way the computer shut down unexpectedly, after i reboot and got connected, all the files can download ok except the big avi file i was downloadind before, it keep connecting to users but cannot download!? however i can search the same file and redownload it again from the begining. But i would like to salvage the .avi file and have it resume downloading, pls advise